Evidence from this program of research demonstrates that psychopaths' failure to profit from punishment and relative inability to inhibit inappropriate behavior are most apparent when they are pursuing a goal of immediate motivational significance. Based on recent neuropsychological models of psychopathy (1, 2), we proposed that availability of reward engenders a motivational state termed "behavioral activation" that potentiates psychopaths' response modulation deficit. The proposed research is designed (1) to address the validity of this hypothesis using both behavioral and psychophysiological measures of the construct; and (2) to explore the means by which behavioral activation contributes to psychopaths' maladaptive response style. We propose to compare the performance of incarcerated psychopaths and controls using five different experimental paradigms. Each paradigm was selected or developed for its ability to elucidate the diverse means by which behavioral activation may contribute to psychopaths' response modulation deficit. Results will clarify the nature of the psychopathic deficit, establish a basis for the early identification and modification of this maladaptive response style, and elucidate the implications of recent neuropsychological models of anxiety and impulsivity for diverse forms of psychopathology involving deficient self-regulation.